@article{RokutanSuckowvonHaehlingetal.2012, author = {Rokutan, Hirofumi and Suckow, Christian and von H{\"a}hling, Stephan and Strassburg, Sabine and Bockmeyer, Barbara and D{\"o}hner, Wolfram and Waller, Christiane and Bauersachs, Johann and von Websky, Karoline and Hocher, Berthold and Anker, Stefan D. and Springer, Jochen}, title = {Furosemide induces mortality in a rat model of chronic heart failure}, series = {International journal of cardiology}, volume = {160}, journal = {International journal of cardiology}, number = {1}, publisher = {Elsevier}, address = {Clare}, issn = {0167-5273}, doi = {10.1016/j.ijcard.2011.03.005}, pages = {20 -- 25}, year = {2012}, abstract = {Objectives: In an experimental heart failure model, we tested the hypothesis that furosemide causes excess mortality. Background: Post-hoc analysis of large clinical heart failure trails revealed that furosemide treatment might be associated with worsening of morbidity and even mortality in heart failure patients. Methods and results: Myocardial infarction was induced in 7 +/- 1 week old male Wistar rats by ligation of the left coronary artery. In study 1, animals were randomly assigned to treatment with furosemide (10 mg/kg/d via drinking water, n = 33) or placebo (n = 33) starting 18 days after surgery. In study 2, animals received furosemide from day 18 and were then randomized to ongoing treatment with either furosemide only (n = 38) or furosemide plus ACE-inhibitor Ramipril (1 mg/kg/d, n = 38) starting on day 42. In study 1 survival rate in the furosemide group was lower than in the placebo group (hazard ratio {HR} 3.39, 95\% confidence interval {CI} 1.14 to 10.09, p = 0.028). The furosemide group had a lower body weight (-6\%, p = 0.028) at the end of the study and a higher sclerosis index of the glomeruli (+9\%, p=0.026) than the placebo group. Wet lung weight, infarct size, and cardiac function were similar between the groups. In study 2, the furosemide group had a higher mortality rate than the furosemide + ramipril group (HR 4.55, 95\% CI 2.0 to 10.0, p = 0.0003). Conclusion: In our rat model of heart failure furosemide, provided at a standard dose, was associated with increased mortality. This increased mortality could be prevented by additional administration of an ACE-inhibitor.}, language = {en} } @article{PrommerMaurervonWebskyetal.2018, author = {Prommer, Hans-Ulrich and Maurer, Johannes and von Websky, Karoline and Freise, Christian and Sommer, Kerstin and Nasser, Hamoud and Samapati, Rudi and Reglin, Bettina and Guimaraes, Pedro and Pries, Axel Radlach and Querfeld, Uwe}, title = {Chronic kidney disease induces a systemic microangiopathy, tissue hypoxia and dysfunctional angiogenesis}, series = {Scientific reports}, volume = {8}, journal = {Scientific reports}, publisher = {Nature Publ. Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-018-23663-1}, pages = {14}, year = {2018}, abstract = {Chronic kidney disease (CKD) is associated with excessive mortality from cardiovascular disease (CVD). Endothelial dysfunction, an early manifestation of CVD, is consistently observed in CKD patients and might be linked to structural defects of the microcirculation including microvascular rarefaction. However, patterns of microvascular rarefaction in CKD and their relation to functional deficits in perfusion and oxygen delivery are currently unknown. In this in-vivo microscopy study of the cremaster muscle microcirculation in BALB/c mice with moderate to severe uremia, we show in two experimental models (adenine feeding or subtotal nephrectomy), that serum urea levels associate incrementally with a distinct microangiopathy. Structural changes were characterized by a heterogeneous pattern of focal microvascular rarefaction with loss of coherent microvascular networks resulting in large avascular areas. Corresponding microvascular dysfunction was evident by significantly diminished blood flow velocity, vascular tone, and oxygen uptake. Microvascular rarefaction in the cremaster muscle paralleled rarefaction in the myocardium, which was accompanied by a decrease in transcription levels not only of the transcriptional regulator HIF-1 alpha, but also of its target genes Angpt-2, TIE-1 and TIE-2, Flkt-1 and MMP-9, indicating an impaired hypoxia-driven angiogenesis. Thus, experimental uremia in mice associates with systemic microvascular disease with rarefaction, tissue hypoxia and dysfunctional angiogenesis.}, language = {en} } @article{vonWebskyHasanReichetzederetal.2018, author = {von Websky, Karoline and Hasan, Ahmed Abdallah Abdalrahman Mohamed and Reichetzeder, Christoph and Tsuprykov, Oleg and Hocher, Berthold}, title = {Impact of vitamin D on pregnancy-related disorders and on offspring outcome}, series = {The Journal of Steroid Biochemistry and Molecular Biology}, volume = {180}, journal = {The Journal of Steroid Biochemistry and Molecular Biology}, publisher = {Elsevier}, address = {Oxford}, issn = {0960-0760}, doi = {10.1016/j.jsbmb.2017.11.008}, pages = {51 -- 64}, year = {2018}, abstract = {Observational studies from all over the world continue to find high prevalence rates of vitamin D insufficiency and deficiency in many populations, including pregnant women. Beyond its classical function as a regulator of calcium and phosphate metabolism, vitamin D elicits numerous effects in the human body. Current evidence highlights a vital role of vitamin D in mammalian gestation. During pregnancy, adaptations in maternal vitamin D metabolism lead to a physiologic increase of vitamin D levels, mainly because of an increased renal production, although other potential sources like the placenta are being discussed. A sufficient supply of mother and child with calcium and vitamin D during pregnancy ensures a healthy bone development of the fetus, whereas lack of either of these nutrients can lead to the development of rickets in the child. Moreover, vitamin D insufficiency during pregnancy has consistently been associated with adverse maternal and neonatal pregnancy outcomes. In multitudinous studies, low maternal vitamin D status was associated with a higher risk for pre-eclampsia, gestational diabetes mellitus and other gestational diseases. Likewise, several negative consequences for the fetus have been reported, including fetal growth restriction, increased risk of preterm birth and a changed susceptibility for later-life diseases. However, study results are diverging and causality has not been proven so far. Meta-analyses on the relationship between maternal vitamin D status and pregnancy outcomes revealed a wide heterogeneity of studied populations and the applied methodology in vitamin D assessment. Until today, clinical guidelines for supplementation cannot be based on high-quality evidence and it is not clear if the required intake for pregnant women differs from non-pregnant women. Long-term safety data of vitamin D supplementation in pregnant women has not been established and overdosing of vitamin D might have unfavorable effects, especially in mothers and newborns with mutations of genes involved in vitamin D metabolism. Reliable data from large observational and interventional randomized control trials are urgently needed as a basis for any detailed and safe recommendations for supplementation in the general population and, most importantly, in pregnant women. This is of utmost importance, as ensuring a sufficient vitamin D-supply of mother and child implies a great potential for the prevention of birth complications and development of diseases.}, language = {en} } @article{HasanvonWebskyReichetzederetal.2019, author = {Hasan, Ahmed Abdallah Abdalrahman Mohamed and von Websky, Karoline and Reichetzeder, Christoph and Tsuprykov, Oleg and Gaballa, Mohamed Mahmoud Salem Ahmed and Guo, Jingli and Zeng, Shufei and Delic, Denis and Tammen, Harald and Klein, Thomas and Kleuser, Burkhard and Hocher, Berthold}, title = {Mechanisms of GLP-1 receptor-independent renoprotective effects of the dipeptidyl peptidase type 4 inhibitor linagliptin in GLP-1 receptor knockout mice with 5/6 nephrectomy}, series = {Kidney international : official journal of the International Society of Nephrology}, volume = {95}, journal = {Kidney international : official journal of the International Society of Nephrology}, number = {6}, publisher = {Elsevier}, address = {New York}, issn = {0085-2538}, doi = {10.1016/j.kint.2019.01.010}, pages = {1373 -- 1388}, year = {2019}, abstract = {Dipeptidyl peptidase type 4 (DPP-4) inhibitors were reported to have beneficial effects in experimental models of chronic kidney disease. The underlying mechanisms are not completely understood. However, these effects could be mediated via the glucagon-like peptide-1 (GLP-1)/GLP-1 receptor (GLP1R) pathway. Here we investigated the renal effects of the DPP-4 inhibitor linagliptin in Glp1r-/- knock out and wild-type mice with 5/6 nephrectomy (5/6Nx). Mice were allocated to groups: sham + wild type + placebo; 5/6Nx+ wild type + placebo; 5/6Nx+ wild type + linagliptin; sham + knock out+ placebo; 5/6Nx + knock out+ placebo; 5/6Nx + knock out+ linagliptin. 5/6Nx caused the development of renal interstitial fibrosis, significantly increased plasma cystatin C and creatinine levels and suppressed renal gelatinase/collagenase, matrix metalloproteinase-1 and -13 activities; effects counteracted by linagliptin treatment in wildtype and Glp1r-/- mice. Two hundred ninety-eight proteomics signals were differentially regulated in kidneys among the groups, with 150 signals specific to linagliptin treatment as shown by mass spectrometry. Treatment significantly upregulated three peptides derived from collagen alpha-1(I), thymosin beta 4 and heterogeneous nuclear ribonucleoprotein Al (HNRNPA1) and significantly downregulated one peptide derived from Y box binding protein-1 (YB-1). The proteomics results were further confirmed using western blot and immunofluorescence microscopy. Also, 5/6Nx led to significant up-regulation of renal transforming growth factor-beta 1 and pSMAD3 expression in wild type mice and linagliptin significantly counteracted this up-regulation in wild type and GIplr-/- mice. Thus, the renoprotective effects of linagliptin cannot solely be attributed to the GLP-1/GLP1R pathway, highlighting the importance of other signaling pathways (collagen I homeostasis, HNRNPA1,YB-1,thymosin beta 4 and TGF-beta 1) influenced by DPP-4 inhibition.}, language = {en} } @article{LuReichetzederPrehnetal.2018, author = {Lu, Yong-Ping and Reichetzeder, Christoph and Prehn, Cornelia and von Websky, Karoline and Slowinski, Torsten and Chen, You-Peng and Yin, Liang-Hong and Kleuser, Burkhard and Yang, Xue-Song and Adamski, Jerzy and Hocher, Berthold}, title = {Fetal serum metabolites are independently associated with Gestational diabetes mellitus}, series = {Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology}, volume = {45}, journal = {Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology}, number = {2}, publisher = {Karger}, address = {Basel}, issn = {1015-8987}, doi = {10.1159/000487119}, pages = {625 -- 638}, year = {2018}, abstract = {Background/Aims: Gestational diabetes (GDM) might be associated with alterations in the metabolomic profile of affected mothers and their offspring. Until now, there is a paucity of studies that investigated both, the maternal and the fetal serum metabolome in the setting of GDM. Mounting evidence suggests that the fetus is not just passively affected by gestational disease but might play an active role in it. Metabolomic studies performed in maternal blood and fetal cord blood could help to better discern distinct fetal from maternal disease interactions. Methods: At the time of birth, serum samples from mothers and newborns (cord blood samples) were collected and screened for 163 metabolites utilizing tandem mass spectrometry. The cohort consisted of 412 mother/child pairs, including 31 cases of maternal GDM. Results: An initial non-adjusted analysis showed that eight metabolites in the maternal blood and 54 metabolites in the cord blood were associated with GDM. After Benjamini-Hochberg (BH) procedure and adjustment for confounding factors for GDM, fetal phosphatidylcholine acyl-alkyl C 32:1 and proline still showed an independent association with GDM. Conclusions: This study found metabolites in cord blood which were associated with GDM, even after adjustment for established risk factors of GDM. To the best of our knowledge, this is the first study demonstrating an independent association between fetal serum metabolites and maternal GDM. Our findings might suggest a potential effect of the fetal metabolome on maternal GDM. (c) 2018 The Author(s) Published by S. Karger AG, Basel}, language = {en} } @misc{AlterOttvonWebskyetal.2011, author = {Alter, Markus L. and Ott, Ina and von Websky, Karoline and Tsuprykov, Oleg and Sharkovska, Yuliya and Krause-Relle, Katharina and Raila, Jens and Henze, Andrea and Kretschmer, Axel and Stasch, Johannes-Peter and Hocher, Berthold}, title = {Additional stimulation of sGC on top of standard treatment with ARB`s may offer a new therapeutic approach for the treatment of diabetic nephropathy resistant to ARB treatment alone}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {855}, issn = {1866-8372}, doi = {10.25932/publishup-42825}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-428250}, pages = {4}, year = {2011}, abstract = {Background Riociguat is the first of a new class of drugs, the soluble guanylate cyclase (sGC) stimulators. Riociguat has a dual mode of action: it sensitizes sGC to the body's own NO and can also increase sGC activity in the absence of NO. The NO-sGC-pathway is impaired in many cardiovascular diseases such as heart failure, pulmonary hypertension and diabetic nephropathy (DN). DN leads to high cardiovascular morbidity and mortality. There is still a high unmet medical need. The urinary albumin excretion rate is a predictive biomarker for these clinical events. Therefore, we investigated the effect of riociguat, alone and in combination with the angiotensin II receptor antagonist (ARB) telmisartan on the progression of DN in diabetic eNOS knock out mice, a new model closely resembling human pathology. Methods Seventy-six male eNOS knockout C57BL/6J mice were divided into 4 groups after receiving intraperitoneal high-dose streptozotocin: telmisartan (1 mg/kg), riociguat (3 mg/kg), riociguat+telmisartan (3 and 1 mg/kg), and vehicle. Fourteen mice were used as non-diabetic controls. After 12 weeks, urine and blood were obtained and blood pressure measured. Glucose concentrations were highly increased and similar in all diabetic groups. Results Riociguat, alone (105.2 ± 2.5 mmHg; mean±SEM; n = 14) and in combination with telmisartan (105.0 ± 3.2 mmHg; n = 12), significantly reduced blood pressure versus diabetic controls (117.1 ± 2.2 mmHg; n = 14; p = 0.002 and p = 0.004, respectively), whereas telmisartan alone (111.2 ± 2.6 mmHg) showed a modest blood pressure lowering trend (p = 0.071; n = 14). The effects of single treatment with either riociguat (97.1 ± 15.7 µg/d; n = 13) or telmisartan (97.8 ± 26.4 µg/d; n = 14) did not significantly lower albumin excretion on its own (p = 0.067 and p = 0.101, respectively). However, the combined treatment led to significantly lower urinary albumin excretion (47.3 ± 9.6 µg/d; n = 12) compared to diabetic controls (170.8 ± 34.2 µg/d; n = 13; p = 0.004), and reached levels similar to non-diabetic controls (31.4 ± 10.1 µg/d, n = 12). Conclusion Riociguat significantly reduced urinary albumin excretion in diabetic eNOS knock out mice that were refractory to treatment with ARB's alone. Patients with diabetic nephropathy refractory to treatment with ARB's have the worst prognosis among all patients with diabetic nephropathy. Our data indicate that additional stimulation of sGC on top of standard treatment with ARB`s may offer a new therapeutic approach for patients with diabetic nephropathy resistant to ARB treatment.}, language = {en} } @article{LuZengChenetal.2013, author = {Lu, Yong-Ping and Zeng, De-Ying and Chen, You-Peng and Liang, Xu-Jing and Xu, Jie-Ping and Huang, Si-Min and Lai, Zhi-Wei and Wen, Wang-Rong and von Websky, Karoline and Hocher, Berthold}, title = {Low birth weight is associated with lower respiratory tract infections in children with hand, foot, and mouth disease}, series = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, volume = {59}, journal = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, number = {9-10}, publisher = {Clin Lab Publ., Verl. Klinisches Labor}, address = {Heidelberg}, issn = {1433-6510}, doi = {10.7754/Clin.Lab.2012.120725}, pages = {985 -- 992}, year = {2013}, abstract = {Background: Low birth weight (LBW) might be a risk factor for acquiring lower respiratory tract infections (LRTIs) associated with disease related complications in early childhood. HFMD, a frequent viral infection in southern China, is a leading cause of lower respiratory tract infections in children. We analyzed whether LBW is a risk factor for children with HFMD to develop lower respiratory tract infections. Methods: A total of 298 children with HFMD, admitted to a hospital in Qingyuan city, Guangdong province, were recruited. Demographic data and clinical parameters such as serum glucose level and inflammatory markers including peripheral white blood cell count, serum C-reactive protein, and erythrocyte sedimentation rate were routinely collected on admission. Birth weight data were derived from birth records. Results: Mean birth weight (BW) was 167 g lower in patients with HFMD and LRTIs as compared to patients with solely HFMD (p = 0.022) and the frequency of birth weight below the tenth percentile was significantly higher in patients with HFMD and LRTIs (p = 0.002). Conclusions: The results of the study show that low birth weight is associated with a higher incidence of lower respiratory tract infections in young children with HFMD.}, language = {en} } @inproceedings{HocherTsuprykovAlteretal.2013, author = {Hocher, Berthold and Tsuprykov, Oleg and Alter, Markus L. and von Websky, Karoline and Chaykovska, Lyubov and Antonenko, V. and Rahnenf{\"u}hrer, Jan and Klein, T. and Reichetzeder, Christoph}, title = {Linagliptin and the angiotensin II receptor blocker telmisartan show comparable efficacy but different renoprotective pathways in rats with 5/6 nephrectomy}, series = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, volume = {56}, booktitle = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, number = {15-16}, publisher = {Springer}, address = {New York}, issn = {0012-186X}, pages = {S66 -- S66}, year = {2013}, language = {en} } @article{ChaykovskaAltervonWebskyetal.2013, author = {Chaykovska, Lyubov and Alter, Markus L. and von Websky, Karoline and Hohmann, Margarete and Tsuprykov, Oleg and Reichetzeder, Christoph and Kutil, Barbara and Kraft, Robin and Klein, Thomas and Hocher, Berthold}, title = {Effects of telmisartan and linagliptin when used in combination on blood pressure and oxidative stress in rats with 2-kidney-1-clip hypertension}, series = {Journal of hypertension}, volume = {31}, journal = {Journal of hypertension}, number = {11}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0263-6352}, doi = {10.1097/HJH.0b013e3283649b4d}, pages = {2290 -- 2299}, year = {2013}, abstract = {Objective:To investigate the effects of linagliptin alone and in combination with the angiotensin II receptor blocker (ARB), telmisartan on blood pressure (BP), kidney function, heart morphology and oxidative stress in rats with renovascular hypertension.Methods:Fifty-seven male Wistar rats underwent unilateral surgical stenosis of the renal artery [2-kidney-1-clip (2k1c) method]. Animals were randomly divided into four treatment groups (n=14-18 per group) receiving: telmisartan (10mg/kg per day in drinking water), linagliptin (89ppm in chow), combination (linagliptin 89ppm+telmisartan 10mg/kg per day) or placebo. An additional group of 12 rats underwent sham surgery. BP was measured one week after surgery. Hypertensive animals entered a 16-week dosing period. BP was measured 2, 4, 8, 12 and 16 weeks after the initiation of treatment. Blood and urine were tested for assessment of kidney function and oxidative stress 6, 10, 14 and 18 weeks after surgery. Blood and urine sampling and organ harvesting were finally performed.Results:Renal stenosis caused an increase in meanSD systolic BP as compared with the sham group (157.7 +/- 29.3 vs. 106.2 +/- 20.5mmHg, respectively; P<0.001). Telmisartan alone and in combination with linagliptin, normalized SBP (111.1 +/- 24.3mmHg and 100.4 +/- 13.9mmHg, respectively; P<0.001 vs. placebo). Telmisartan alone and in combination with linagliptin significantly prevented cardiac hypertrophy, measured by heart weight and myocyte diameter. Renal function measured by cystatin C was not affected by 2k1c surgery. Telmisartan significantly increased plasma concentration of cystatin C. 2k1c surgery initiated fibrosis in both kidneys. Telmisartan promoted further fibrotic changes in the clipped kidney, as measured by protein expression of Col1a1 and histology for interstitial fibrosis and glomerulosclerosis. In non-clipped kidneys, telmisartan demonstrated antifibrotic properties, reducing Col1a1 protein expression. Plasma levels of oxidized low-density lipoprotein were higher in the placebo-treated 2k1c rats as compared to sham-operated animals. The increase was abolished by linagliptin alone (P=0.03 vs. placebo) and in combination with telmisartan (P=0.02 vs. placebo). Combination therapy also significantly reduced plasma concentration of carbonyl proteins (P=0.04 vs. placebo).Conclusion:Inhibition of type 4 dipeptidyl peptidase with linagliptin did not counter BP-lowering effects of ARB in 2k1c rats. Linagliptin reduced lipid and protein oxidation in 2k1c rats, and this effect was BP-independent.}, language = {en} } @article{HocherHeidenvonWebskyetal.2011, author = {Hocher, Berthold and Heiden, S. and von Websky, Karoline and Rahnenf{\"u}hrer, J{\"o}rg and Kalk, Philipp and Pfab, T.}, title = {Dual endothelin-converting enzyme/neutral endopeptidase blockade in rats with D-galactosamine-induced liver failure}, series = {European journal of medical research : official organ "Deutsche AIDS-Gesellschaft"}, volume = {16}, journal = {European journal of medical research : official organ "Deutsche AIDS-Gesellschaft"}, number = {6}, publisher = {Med. Scientific Publ. Holzapfel}, address = {M{\"u}nchen}, issn = {0949-2321}, pages = {275 -- 279}, year = {2011}, abstract = {Secondary activation of the endothelin system is thought to be involved in toxic liver injury. This study tested the hypothesis that dual endothelin-converting enzyme / neutral endopeptidase blockade might: be able to attenuate acute toxic liver injury. Male Sprague-Dawley rats were implanted with subcutaneous minipumps to deliver the novel compound SLV338 (10 mg/kg*d) or vehicle. Four days later they received two intraperitoneal injections of D-galactosamine (1.3 g/kg each) or vehicle at an interval of 12 hours. The animals were sacrificed 48 hours after the first injection. Injection of D-galactosamine resulted in very severe liver injury, reflected by strongly elevated plasma liver enzymes, hepatic necrosis and inflammation, and a mortality rate of 42.9 \%. SLV338 treatment did not show any significant effect on the extent of acute liver injury as judged from plasma parameters, hepatic histology and mortality. Plasma measurements of SLV338 confirmed adequate drug delivery. Plasma concentrations of big endothelin-1 and endothelin-1 were significantly elevated in animals with liver injury (5-fold and 62-fold, respectively). Plasma endothelin-1 was significantly correlated with several markers of liver injury. SLV338 completely prevented the rise of plasma big endothelin-1 (p<0.05) and markedly attenuated the rise of endothelin-1 (p = 0.055). In conclusion, dual endothelin-converting enzyme / neutral endopeptidase blockade by SLV338 did not significantly attenuate D-galactosamine-induced acute liver injury, although it largely prevented the activation of the endothelin system. An evaluation of SLV338 in a less severe model of liver injury would be of interest, since very severe intoxication might not be relevantly amenable to pharmacological interventions.}, language = {en} } @inproceedings{HocherReichetzedervonWebskyetal.2014, author = {Hocher, Berthold and Reichetzeder, Christoph and von Websky, Karoline and Tsuprykov, Oleg and Klein, T.}, title = {Dipeptidyl peptidase-4 inhibition in a rat model of ischaemia-reperfusion injury may accelerate tubular regeneration but does not improve glomerular filtration rate}, series = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, volume = {57}, booktitle = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, publisher = {Springer}, address = {New York}, issn = {0012-186X}, pages = {S538 -- S538}, year = {2014}, language = {en} } @inproceedings{ReichetzederPaschvonWebskyetal.2014, author = {Reichetzeder, Christoph and Pasch, A. and von Websky, Karoline and Tsuprykov, Oleg and Klein, T. and Hocher, Berthold}, title = {The DPP-4 inhibitor linagliptin increases plasma fetuin-A concentrations in a rat model of uraemic calcification}, series = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, volume = {57}, booktitle = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, publisher = {Springer}, address = {New York}, issn = {0012-186X}, pages = {S522 -- S522}, year = {2014}, language = {en} } @article{PutraTsuprykovVonWebskyetal.2014, author = {Putra, Sulistyo Emantoko Dwi and Tsuprykov, Oleg and Von Websky, Karoline and Ritter, Teresa and Reichetzeder, Christoph and Hocher, Berthold}, title = {Dealing with large sample sizes: comparison of a new one spot dot blot method to western blot}, series = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, volume = {60}, journal = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, number = {11}, publisher = {Clin Lab Publ., Verl. Klinisches Labor}, address = {Heidelberg}, issn = {1433-6510}, doi = {10.7754/Clin.Lab.2014.140317}, pages = {1871 -- 1877}, year = {2014}, abstract = {Background: Western blot is the gold standard method to determine individual protein expression levels. However, western blot is technically difficult to perform in large sample sizes because it is a time consuming and labor intensive process. Dot blot is often used instead when dealing with large sample sizes, but the main disadvantage of the existing dot blot techniques, is the absence of signal normalization to a housekeeping protein. Methods: In this study we established a one dot two development signals (ODTDS) dot blot method employing two different signal development systems. The first signal from the protein of interest was detected by horseradish peroxidase (HRP). The second signal, detecting the housekeeping protein, was obtained by using alkaline phosphatase (AP). Results: Inter-assay results variations within ODTDS dot blot and western blot and intra-assay variations between both methods were low (1.04 - 5.71\%) as assessed by coefficient of variation. Conclusions: ODTDS dot blot technique can be used instead of western blot when dealing with large sample sizes without a reduction in results accuracy.}, language = {en} } @article{ChenWangWangetal.2014, author = {Chen, Yao and Wang, Guang and Wang, Xiao-yu and Ma, Zheng-lai and Chen, You-peng and Chuai, Manli and von Websky, Karoline and Hocher, Berthold and Yang, Xuesong}, title = {Effects of high salt-exposure on the development of retina and lens in 5.5-Day Chick Embryo}, series = {Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology}, volume = {34}, journal = {Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry and pharmacology}, number = {3}, publisher = {Karger}, address = {Basel}, issn = {1015-8987}, doi = {10.1159/000363044}, pages = {804 -- 817}, year = {2014}, abstract = {Background/Aims: Excess maternal salt intake during pregnancy may alter fetal development. However; our knowledge on how an increased salt intake during pregnancy influences fetal eye development is limited. In this study, we investigated the effects of high salt treatment on the developing eyes in chick embryos, especially focusing on the development of the retina and the lens. Methods: 5.5 day chick embryos were exposed to 280mosm/l (n=17), or 300mosm/l (n=16) NaCl. The treated embryos were then incubated for 96 hours before they were fixed with 4\% paraformaldehyde for H\&E staining, whole mount embryo immunostaining and TUNEL staining. BrdU and PH3 incorporation experiments were performed on the chick embryos after high salt treatment. RT-PCR analyses were conducted from chick retina tissues. Results: We demonstrated that high-salt treatment altered the size of eyes in chick embryos, induced malformation of the eyes and impaired the development of the lens and the retina. We found an impaired expression of Paired box 6 (PAX6) and neuronal cells in the developing retina as revealed by neurofilament immunofluorescent staining. There was a reduction in the number of BrdU-positive cells and PH3-positive cells in the retina, indicating an impaired cell proliferation with high salt treatment. High salt treatment also resulted in an increased number of TUNEL-positive cells in the retina, indicating a higher amount of cell death. RT-PCR data displayed that the expression of the pro-apoptotic molecule nerve growth factor (NGF) in chick retina was increased and CyclinD1 was reduced with high-salt treatment. The size of the lens was reduced and Pax6 expression in the lens was significantly inhibited. High salt treatment was detrimental to the migration of neural crest cells. Conclusion: Taken together; our study demonstrated that high salt exposure of 5.5 day chick embryos led to an impairment of retina and lens development, possibly through interfering with Pax6 expression.}, language = {en} } @article{ChaykovskavonWebskyRahnenfuehreretal.2011, author = {Chaykovska, Lyubov and von Websky, Karoline and Rahnenf{\"u}hrer, Jan and Alter, Markus L. and Heiden, Susi and Fuchs, Holger and Runge, Frank and Klein, Thomas and Hocher, Berthold}, title = {Effects of DPP-4 Inhibitors on the Heart in a Rat Model of Uremic Cardiomyopathy}, series = {PLoS one}, volume = {6}, journal = {PLoS one}, number = {11}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0027861}, pages = {9}, year = {2011}, abstract = {Background: Uremic cardiomyopathy contributes substantially to mortality in chronic kidney disease (CKD) patients. Glucagon-like peptide-1 (GLP-1) may improve cardiac function, but is mainly degraded by dipeptidyl peptidase-4 (DPP-4). Methodology/Principal Findings: In a rat model of chronic renal failure, 5/6-nephrectomized [5/6N] rats were treated orally with DPP-4 inhibitors (linagliptin, sitagliptin, alogliptin) or placebo once daily for 4 days from 8 weeks after surgery, to identify the most appropriate treatment for cardiac dysfunction associated with CKD. Linagliptin showed no significant change in blood level AUC(0-infinity) in 5/6N rats, but sitagliptin and alogliptin had significantly higher AUC(0-infinity) values; 41\% and 28\% (p=0.0001 and p=0.0324), respectively. No correlation of markers of renal tubular and glomerular function with AUC was observed for linagliptin, which required no dose adjustment in uremic rats. Linagliptin 7 mu mol/kg caused a 2-fold increase in GLP-1 (AUC 201.0 ng/l*h) in 5/6N rats compared with sham-treated rats (AUC 108.6 ng/l*h) (p=0.01). The mRNA levels of heart tissue fibrosis markers were all significantly increased in 5/6N vs control rats and reduced/normalized by linagliptin. Conclusions/Significance: DPP-4 inhibition increases plasma GLP-1 levels, particularly in uremia, and reduces expression of cardiac mRNA levels of matrix proteins and B-type natriuretic peptides (BNP). Linagliptin may offer a unique approach for treating uremic cardiomyopathy in CKD patients, with no need for dose-adjustment.}, language = {en} } @article{OttAltervonWebskyetal.2012, author = {Ott, Ina M. and Alter, Markus L. and von Websky, Karoline and Kretschmer, Axel and Tsuprykov, Oleg and Sharkovska, Yuliya and Krause-Relle, Katharina and Raila, Jens and Henze, Andrea and Stasch, Johannes-Peter and Hocher, Berthold}, title = {Effects of Stimulation of Soluble Guanylate Cyclase on Diabetic Nephropathy in Diabetic eNOS Knockout Mice on Top of Angiotensin II Receptor Blockade}, series = {PLOS ONE}, volume = {7}, journal = {PLOS ONE}, number = {8}, publisher = {PUBLIC LIBRARY SCIENCE}, address = {SAN FRANCISCO}, issn = {1932-6203}, doi = {10.1371/journal.pone.0042623}, pages = {9}, year = {2012}, abstract = {The prevalence of diabetes mellitus and its complications, such as diabetic nephropathy (DN), is rising worldwide and prevention and treatment are therefore becoming increasingly important. Therapy of DN is particularly important for patients who do not adequately respond to angiotensin receptor blocker (ARB) treatment. Novel approaches include the stimulation of soluble guanylate cyclase (sGC) as it is reported to have beneficial effects on cardiac and renal damage. We aimed to investigate the effects of the sGC stimulator riociguat and ARB telmisartan on kidney function and structure in a hypertensive model of diabetic nephropathy. Seventy-six diabetic male eNOS knockout C57BL/6J mice were randomly divided after having received streptozotocin: telmisartan (1 mg/kg/d), riociguat (3 mg/kg/d), riociguat+telmisartan (3+1 mg/kg/d), and vehicle. Fourteen mice were used as non-diabetic controls. Treatment duration was 11 weeks. Glucose concentrations were increased and similar in all diabetic groups. Telmisartan insignificantly reduced blood pressure by 5.9 mmHg compared with diabetic controls (111.2 +/- 2.3 mmHg vs. 117.1 +/- 2.2 mmHg; p = 0.071). Treatment with riociguat both alone and in combination with telmisartan led to a significant reduction of blood pressure towards diabetic vehicle (105.2 +/- 2.5 mmHg and 105.0 +/- 3.2 mmHg, respectively, vs. 117.1 +/- 2.2 mmHg). Combined treatment also significantly decreased albuminuria compared with diabetic controls (47.3 +/- 9.6 mu g/24 h vs. 170.8 +/- 34.2 mu g/24 h; p = 0.002) reaching levels similar to those of non-diabetic controls (34.4 +/- 10.6 mu g/24 h), whereas the reduction by single treatment with either telmisartan (97.8 +/- 26.4 mu g/24 h) or riociguat (97.1 +/- 15.7 mu g/24 h) was not statistically significant. The combination treatment led to a significant (p < 0.01) decrease of tissue immunoreactivity of malondialdehyde, as consequence of reduced oxidative stress. In conclusion, stimulation of sGC significantly reduced urinary albumin excretion in diabetic eNOS knockout mice treated already with ARB. Thus, this new drug class on top of standard ARBs administration may offer a new therapeutic approach for patients resistant to ARB treatment.}, language = {en} } @article{AlterKretschmerVonWebskyetal.2012, author = {Alter, Markus L. and Kretschmer, Axel and Von Websky, Karoline and Tsuprykov, Oleg and Reichetzeder, Christoph and Simon, Alexandra and Stasch, Johannes-Peter and Hocher, Berthold}, title = {Early urinary and plasma biomarkers for experimental diabetic Nephropathy}, series = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, volume = {58}, journal = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, number = {7-8}, publisher = {Clin Lab Publ., Verl. Klinisches Labor}, address = {Heidelberg}, issn = {1433-6510}, doi = {10.7754/Clin.Lab.2011.111010}, pages = {659 -- 671}, year = {2012}, abstract = {Background: As the prevalence of diabetes rises, its complications such as diabetic nephropathy affect an increaseing number of patients. Consequently, the need for biomarkers in rodent models which reflect the stage and course of diabetic nephropathy is high. This article focuses on Heart-type fatty acid binding protein (H-FABP), osteopontin (OPN), nephrin, and Neutrophil gelatinase-associated lipocalin (NGAL) in urine, and kidney injury molecule (KIM)-1, clusterin, and tissue inhibitior of metalloproteinases (TIMP) 1 in plasma in uni-nephrectomized rats with streptocotozin-induced type 1 diabetes mellitus, a common animal model to explore renal impairment in the setting of diabetes mellitus. Methods: 23 male Wistar rats were uni-nephrectomized and subsequently divided into two study groups. The diabetic group received streptozotocin (STZ) via tail-vein injection, the non-diabetic group received citrate buffer without STZ. Subsequently, blood glucose, body weight, and blood pressure were checked regularly. After 18 weeks, animals were placed in metabolic cages, blood and urine obtained and subsequently organs were harvested after sacrifice. Results: Blood glucose levels were highly increased in diabetic animals throughout the experiment, whereas systolic blood pressure did not differ between the study groups. At study end, classical biomarkers such as urinary albumin and protein and plasma cystatin c were only slightly but not significantly different between groups indicating a very early disease state. In contrast, urinary excretion of H-FABP, OPN, nephrin, and NGAL were highly increased in diabetic animals with a highly significant p-value (p<0.01 each) compared to non-diabetic animals. In plasma, differences were found for calbindin, KIM-1, clusterin, TIMP-1, and OPN. These findings were confirmed by means of the area under the receiver operating characteristic curve (ROC-AUC) analysis. Conclusions: In summary, our study revealed elevated levels of new plasma and urinary biomarkers (urinary osteopontin, urinary nephrin, urinary NGAL, urinary H-FABP, plasma KIM-1, plasma TIMP-1) in uni-nephrectomized diabetic rats, an established rat model of diabetic nephropathy. These biomarkers appeared even before the classical biomarkers of diabetic nephropathy such as albuminuria and urinary protein excretion. The new biomarkers might offer advantage to urinary albumin and plasma cystatin c with respect to early detection.}, language = {en} } @article{KalkSharkovskaKashinaetal.2011, author = {Kalk, Philipp and Sharkovska, Yuliya and Kashina, Elena and von Websky, Karoline and Relle, Katharina and Pfab, Thiemo and Alter, Markus L. and Guillaume, Philippe and Provost, Daniel and Hoffmann, Katrin and Fischer, Yvan and Hocher, Berthold}, title = {Endothelin-Converting Enzyme/Neutral Endopeptidase Inhibitor SLV338 Prevents Hypertensive Cardiac Remodeling in a Blood Pressure-Independent Manner}, series = {HYPERTENSION}, volume = {57}, journal = {HYPERTENSION}, number = {4}, publisher = {LIPPINCOTT WILLIAMS \& WILKINS}, address = {PHILADELPHIA}, issn = {0194-911X}, doi = {10.1161/HYPERTENSIONAHA.110.163972}, pages = {755 -- 763}, year = {2011}, abstract = {Hypertensive heart disease is a major contributor to cardiovascular mortality. Endothelin is a potent vasoconstrictive and profibrotic mediator produced by the endothelin-converting enzyme (ECE), whereas natriuretic peptides, degraded by the neutral endopeptidase (NEP), have diuretic, vasodilatory, and antifibrotic properties. Thus, combined ECE/NEP inhibition may halt hypertensive cardiac remodeling. This study examined effects of SLV338, a novel ECE/NEP inhibitor, on cardiac protection in experimental renovascular hypertension (2-kidney, 1-clip [2K1C]). Male rats were allocated to 5 groups: sham-operated rats, untreated animals with 2K1C, 2K1C animals treated with oral SLV338 (30 and 100 mg/kg per day), and 2K1C animals treated with oral losartan (20 mg/kg per day). Treatment duration was 12 weeks. Blood pressure was assessed every 4 weeks. At study end, hearts were taken for histology/computer-aided histomorphometry/immunohistochemistry. Pharmacological properties of SLV338 are described. SLV338 is a dual ECE/NEP inhibitor, as demonstrated both in vitro and in vivo. In the 2K1C study, losartan lowered blood pressure by <= 46 mm Hg, whereas both dosages of SLV338 had no effect. However, SLV338 (both dosages) completely normalized cardiac interstitial fibrosis, perivascular fibrosis, myocyte diameter, and media: lumen ratio of cardiac arteries, as did losartan. Cardiac transforming growth factor-beta 1 expression was significantly enhanced in untreated 2K1C rats versus controls, whereas treatment with SLV338 and losartan prevented this effect. Taken together, dual ECE/NEP inhibitor SLV338 prevents cardiac remodeling to the same extent as losartan, but in a blood pressure-independent manner, in a rat model of renovascular hypertension. This effect is at least partially mediated via suppression of cardiac transforming growth factor-beta 1 expression. (Hypertension. 2011;57:755-763.)}, language = {en} } @inproceedings{ReichetzedervonWebskyTsuprykovetal.2015, author = {Reichetzeder, Christoph and von Websky, Karoline and Tsuprykov, Oleg and Antonenko, V. and Samarin, Azin Mohagheghi and Hocher, Berthold}, title = {Effects of DPP-4 inhibition on glomerular and tubular function in a rat model of ischaemia-reperfusion injury}, series = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, volume = {58}, booktitle = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, publisher = {Springer}, address = {New York}, issn = {0012-186X}, pages = {S34 -- S35}, year = {2015}, language = {en} } @inproceedings{PfabSharkovskaAlteretal.2011, author = {Pfab, T. and Sharkovska, Yukiya and Alter, Markus L. and von Websky, Karoline and Mark, M. and Klein, T. and Hocher, Berthold}, title = {Effect of linagliptin on infarction size and cardiac function in rats after myocardial ischaemia reperfusion}, series = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, volume = {54}, booktitle = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, publisher = {Springer}, address = {New York}, issn = {0012-186X}, pages = {S329 -- S329}, year = {2011}, language = {en} } @article{HocherHeidenvonWebskyetal.2011, author = {Hocher, Berthold and Heiden, Susi and von Websky, Karoline and Arafat, Ayman M. and Rahnenf{\"u}hrer, Jan and Alter, Markus L. and Kalk, Philipp and Ziegler, Dieter and Fischer, Yvan and Pfab, Thiemo}, title = {Renal effects of the novel selective adenosine A(1) receptor blocker SLV329 in experimental liver cirrhosis in rats}, series = {PLoS one}, volume = {6}, journal = {PLoS one}, number = {3}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0017891}, pages = {8}, year = {2011}, abstract = {Liver cirrhosis is often complicated by an impaired renal excretion of water and sodium. Diuretics tend to further deteriorate renal function. It is unknown whether chronic selective adenosine A(1) receptor blockade, via inhibition of the hepatorenal reflex and the tubuloglomerular feedback, might exert diuretic and natriuretic effects without a reduction of the glomerular filtration rate. In healthy animals intravenous treatment with the novel A(1) receptor antagonist SLV329 resulted in a strong dose-dependent diuretic (up to 3.4-fold) and natriuretic (up to 13.5-fold) effect without affecting creatinine clearance. Male Wistar rats with thioacetamide-induced liver cirrhosis received SLV329, vehicle or furosemide for 12 weeks. The creatinine clearance of cirrhotic animals decreased significantly (-36.5\%, p < 0.05), especially in those receiving furosemide (-41.9\%, p < 0.01). SLV329 was able to prevent this decline of creatinine clearance. Mortality was significantly lower in cirrhotic animals treated with SLV329 in comparison to animals treated with furosemide (17\% vs. 54\%, p < 0.05). SLV329 did not relevantly influence the degree of liver fibrosis, kidney histology or expression of hepatic or renal adenosine receptors. In conclusion, chronic treatment with SLV329 prevented the decrease of creatinine clearance in a rat model of liver cirrhosis. Further studies will have to establish whether adenosine A(1) receptor antagonists are clinically beneficial at different stages of liver cirrhosis.}, language = {en} } @article{AlterOttvonWebskyetal.2012, author = {Alter, Markus L. and Ott, Ina M. and von Websky, Karoline and Tsuprykov, Oleg and Sharkovska, Yuliya and Krause-Relle, Katharina and Raila, Jens and Henze, Andrea and Klein, Thomas and Hocher, Berthold}, title = {DPP-4 Inhibition on top of angiotensin receptor blockade offers a new therapeutic approach for diabetic nephropathy}, series = {Kidney \& blood pressure research : official organ of the Gesellschaft f{\"u}r Nephrologie}, volume = {36}, journal = {Kidney \& blood pressure research : official organ of the Gesellschaft f{\"u}r Nephrologie}, number = {1}, publisher = {Karger}, address = {Basel}, issn = {1420-4096}, doi = {10.1159/000341487}, pages = {119 -- 130}, year = {2012}, abstract = {Background: The need for an improved treatment for diabetic nephropathy is greatest in patients who do not adequately respond to angiotensin II receptor blockers (ARBs). This study investigated the effect of the novel dipeptidyl peptidase-4 inhibitor linagliptin alone and in combination with the ARB telmisartan on the progression of diabetic nephropathy in diabetic endothelial nitric oxide synthase (eNOS) knockout mice. Methods: Sixty male eNOS knockout C57BL/6J mice were divided into four groups after receiving intraperitoneal high-dose streptozotocin: telmisartan (1 mg/kg), linagliptin (3 mg/kg), linagliptin + telmisartan (3 mg/kg + 1 mg/kg) and vehicle. Fourteen mice were used as non-diabetic controls. Results: After 12 weeks, urine and blood were obtained and blood pressure measured. Glucose concentrations were increased and similar in all diabetic groups. Telmisartan alone reduced systolic blood pressure by 5.9 mmHg versus diabetic controls (111.2 +/- 2.3 mmHg vs 117.1 +/- 2.2 mmHg; mean +/- SEM; P = 0.071). Combined treatment significantly reduced albuminuria compared with diabetic controls (71.7 +/- 15.3 mu g/24 h vs 170.8 +/- 34.2 mu g/24 h; P = 0.017), whereas the effects of single treatment with either telmisartan (97.8 +/- 26.4 mu g/24 h) or linagliptin (120.8 +/- 37.7 mu g/24 h) were not statistically significant. DPP-4 inhibition, alone and in combination, led to significantly lower plasma osteopontin levels compared with telmisartan alone. Histological analysis revealed reduced glomerulosclerosis after Linagliptin alone and in combination with telmisartan in comparison to non treated diabetic animals (p < 0.01 and p < 0.05). Kidney malonaldehyde immune-reactivity, a marker of oxidative stress, was significantly lower in animals treated with linagliptin. Conclusions: DPP-4 inhibition on top of ARB treatment significantly reduced urinary albumin excretion and oxidative stress in diabetic eNOS knockout mice. Linagliptin on top of an angiotensin II receptor blocker may offer a new therapeutic approach for patients with diabetic nephropathy.}, language = {en} } @article{SharkovskaKalkvonWebskyetal.2011, author = {Sharkovska, Yuliya and Kalk, Philipp and von Websky, Karoline and Relle, Katharina and Pfab, Thiemo and Alter, Markus L. and Fischer, Yvan and Hocher, Berthold}, title = {Renoprotective effects of combined endothelin-converting enzyme/neutral endopeptidase inhibitor SLV338 in acute and chronic experimental renal damage}, series = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, volume = {57}, journal = {Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion}, number = {7-8}, publisher = {Clin Lab Publ., Verl. Klinisches Labor}, address = {Heidelberg}, issn = {1433-6510}, pages = {507 -- 515}, year = {2011}, abstract = {Background: Acute kidney injury (AKI) as well as chronic renal failure are associated with a huge mortality/morbidity. However, so far no drugs have been approved for the treatment of acute kidney failure and only a few for the treatment of chronic kidney disease (CKD). We analysed the effect of SLV 338, a neutral endopeptidase (NEP)/endothelin converting enzyme (ECE)-inhibitor in animal models of acute kidney failure as well as chronic renal failure. Methods: Acute renal failure was induced in male Wistar rats by uninephrectomy and clamping of the remaining kidney for 55 minutes. SLV338 (total dose: 4.9 mg/kg) or vehicle was continuously infused for 2 hours (starting 20 minutes prior to clamping). Sham operated animals served as controls. Plasma creatinine was measured at baseline and day 2 and 8 after renal ischemia-reperfusion. Hypertensive renal damage was induced in male Sprague Dawley rats by nitric oxide deficiency using L-NAME (50 mg/kg per day, added to drinking water for 4 weeks). One group was treated over the same time period with SLV338 (30 mg/kg per day, mixed with food). Systolic blood pressure was monitored weekly. At study end, urine and blood samples were collected and kidneys were harvested. Results: Acute renal ischemia-reperfusion caused a 5-fold plasma creatinine elevation (day 2), which was significantly attenuated by more than 50 \% in animals treated with SLV338 (p < 0.05). Renal failure was accompanied by a 67 \% mortality in vehicle-treated rats, but only 20 \% after SLV338 treatment (p = 0.03 compared to sham controls). Chronic L-NAME administration caused hypertension, urinary albumin excretion, glomerulosclerosis, renal arterial remodelling, and renal interstitial fibrosis. Treatment with SLV338 did not significantly affect blood pressure, but abolished renal tissue damage (interstitial fibrosis, glomerulosclerosis, renal arterial remodelling (p < 0.05 versus L-NAME group in each case). Conclusions: The dual ECE/NEP inhibitor SLV338 preserves kidney function and reduces mortality in severe acute ischemic renal failure. Moreover, combined ECE/NEP inhibition prevents hypertensive renal tissue damage in a blood pressure independent manner in L-NAME-treated rats.}, language = {en} } @misc{vonWebskyReichetzederHocher2014, author = {von Websky, Karoline and Reichetzeder, Christoph and Hocher, Berthold}, title = {Physiology and pathophysiology of incretins in the kidney}, series = {Current opinion in nephrology and hypertension : reviews of all advances, evaluations of key references, comprehensive listing of papers}, volume = {23}, journal = {Current opinion in nephrology and hypertension : reviews of all advances, evaluations of key references, comprehensive listing of papers}, number = {1}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {1062-4821}, doi = {10.1097/01.mnh.0000437542.77175.a0}, pages = {54 -- 60}, year = {2014}, abstract = {Purpose of reviewIncretin-based therapy with glucagon-like peptide-1 receptor (GLP-1R) agonists and dipeptidyl peptidase-4 (DPP-4) inhibitors is considered a promising therapeutic option for type 2 diabetes mellitus. Cumulative evidence, mainly from preclinical animal studies, reveals that incretin-based therapies also may elicit beneficial effects on kidney function. This review gives an overview of the physiology, pathophysiology, and pharmacology of the renal incretin system.Recent findingsActivation of GLP-1R in the kidney leads to diuretic and natriuretic effects, possibly through direct actions on renal tubular cells and sodium transporters. Moreover, there is evidence that incretin-based therapy reduces albuminuria, glomerulosclerosis, oxidative stress, and fibrosis in the kidney, partially through GLP-1R-independent pathways. Molecular mechanisms by which incretins exert their renal effects are understood incompletely, thus further studies are needed.SummaryThe GLP-1R and DPP-4 are expressed in the kidney in various species. The kidney plays an important role in the excretion of incretin metabolites and most GLP-1R agonists and DPP-4 inhibitors, thus special attention is required when applying incretin-based therapy in renal impairment. Preclinical observations suggest direct renoprotective effects of incretin-based therapies in the setting of hypertension and other disorders of sodium retention, as well as in diabetic and nondiabetic nephropathy. Clinical studies are needed in order to confirm translational relevance from preclinical findings for treatment options of renal diseases.}, language = {en} } @misc{LuReichetzederPrehnetal.2018, author = {Lu, Yong-Ping and Reichetzeder, Christoph and Prehn, Cornelia and von Websky, Karoline and Slowinski, Torsten and Chen, You-Peng and Yin, Liang-Hong and Kleuser, Burkhard and Yang, Xue-Song and Adamski, Jerzy and Hocher, Berthold}, title = {Fetal serum metabolites are independently associated with Gestational diabetes mellitus}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {637}, issn = {1866-8372}, doi = {10.25932/publishup-42458}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-424585}, pages = {14}, year = {2018}, abstract = {Background/Aims: Gestational diabetes (GDM) might be associated with alterations in the metabolomic profile of affected mothers and their offspring. Until now, there is a paucity of studies that investigated both, the maternal and the fetal serum metabolome in the setting of GDM. Mounting evidence suggests that the fetus is not just passively affected by gestational disease but might play an active role in it. Metabolomic studies performed in maternal blood and fetal cord blood could help to better discern distinct fetal from maternal disease interactions. Methods: At the time of birth, serum samples from mothers and newborns (cord blood samples) were collected and screened for 163 metabolites utilizing tandem mass spectrometry. The cohort consisted of 412 mother/child pairs, including 31 cases of maternal GDM. Results: An initial non-adjusted analysis showed that eight metabolites in the maternal blood and 54 metabolites in the cord blood were associated with GDM. After Benjamini-Hochberg (BH) procedure and adjustment for confounding factors for GDM, fetal phosphatidylcholine acyl-alkyl C 32:1 and proline still showed an independent association with GDM. Conclusions: This study found metabolites in cord blood which were associated with GDM, even after adjustment for established risk factors of GDM. To the best of our knowledge, this is the first study demonstrating an independent association between fetal serum metabolites and maternal GDM. Our findings might suggest a potential effect of the fetal metabolome on maternal GDM. (c) 2018 The Author(s) Published by S. Karger AG, Basel}, language = {en} } @article{HechtFreisevonWebskyetal.2016, author = {Hecht, Eva and Freise, Christian and von Websky, Karoline and Nasser, Hamoud and Kretzschmar, Nadja and Stawowy, Philipp and Hocher, Berthold and Querfeld, Uwe}, title = {The matrix metalloproteinases 2 and 9 initiate uraemic vascular calcifications}, series = {Nephrology, dialysis, transplantation}, volume = {31}, journal = {Nephrology, dialysis, transplantation}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0931-0509}, doi = {10.1093/ndt/gfv321}, pages = {789 -- 797}, year = {2016}, abstract = {The matrix metalloproteinases (MMP) MMP-2 and MMP-9 are physiological regulators of vascular remodelling. Their dysregulation could contribute to vascular calcification. We examined the role of the MMP-2 and MMP-9 in uraemic vascular calcification in vivo and in vitro. The impact of pharmacological MMP inhibition on the development of media calcifications was explored in an aggressive animal model of uraemic calcification. In addition, the selective effects of addition and inhibition, respectively, of MMP-2 and MMP-9 on calcium-/phosphate-induced calcifications were studied in a murine cell line of vascular smooth muscle cells (VSMCs). High-dose calcitriol treatment of uraemic rats given a high phosphate diet induced massive calcifications, apoptosis and increased gene expressions of MMP-2, MMP-9 and of osteogenic transcription factors and proteins in aortic VSMC. The MMP inhibitor doxycycline prevented the VSMC transdifferentiation to osteoblastic cells, suppressed transcription of mediators of matrix remodelling and almost completely blocked aortic calcifications while further increasing apoptosis. Similarly, specific inhibitors of either MMP-2 or -9, or of both gelatinases (Ro28-2653) and a selective knockdown of MMP-2/-9 mRNA expression blocked calcification of murine VSMC induced by calcification medium (CM). In contrast to MMP inhibition, recombinant MMP-2 or MMP-9 enhanced CM-induced calcifications and the secretion of gelatinases. These data indicate that both gelatinases provide essential signals for phenotypic VSMC conversion, matrix remodelling and the initiation of vascular calcification. Their inhibition seems a promising strategy in the prevention of vascular calcifications.}, language = {en} } @article{TsuprykovAndoReichetzederetal.2016, author = {Tsuprykov, Oleg and Ando, Ryotaro and Reichetzeder, Christoph and von Websky, Karoline and Antonenko, Viktoriia and Sharkovska, Yuliya and Chaykovska, Lyubov and Rahnenfuehrer, Jan and Hasan, Ahmed Abdallah Abdalrahman Mohamed and Tammen, Harald and Alter, Markus L. and Klein, Thomas and Ueda, Seiji and Yamagishi, Sho-ichi and Okuda, Seiya and Hocher, Berthold}, title = {The dipeptidyl peptidase inhibitor linagliptin and the angiotensin II receptor blocker telmisartan show renal benefit by different pathways in rats with 5/6 nephrectomy}, series = {Kidney international : official journal of the International Society of Nephrology}, volume = {89}, journal = {Kidney international : official journal of the International Society of Nephrology}, publisher = {Nature Publ. Group}, address = {New York}, issn = {0085-2538}, doi = {10.1016/j.kint.2016.01.016}, pages = {1049 -- 1061}, year = {2016}, abstract = {Dipeptidyl peptidase (DPP)-4 inhibitors delay chronic kidney disease (CKD) progression in experimental diabetic nephropathy in a glucose-independent manner. Here we compared the effects of the DPP-4 inhibitor linagliptin versus telmisartan in preventing CKD progression in non-diabetic rats with 5/6 nephrectomy. Animals were allocated to 1 of 4 groups: sham operated plus placebo; 5/6 nephrectomy plus placebo; 5/6 nephrectomy plus linagliptin; and 5/6 nephrectomy plus telmisartan. Interstitial fibrosis was significantly decreased by 48\% with linagliptin but a non-significant 24\% with telmisartan versus placebo. The urine albumin-to-creatinine ratio was significantly decreased by 66\% with linagliptin and 92\% with telmisartan versus placebo. Blood pressure was significantly lowered by telmisartan, but it was not affected by linagliptin. As shown by mass spectrometry, the number of altered peptide signals for linagliptin in plasma was 552 and 320 in the kidney. For telmisartan, there were 108 peptide changes in plasma and 363 in the kidney versus placebo. Linagliptin up-regulated peptides derived from collagen type I, apolipoprotein C1, and heterogeneous nuclear ribonucleoproteins A2/B1, a potential downstream target of atrial natriuretic peptide, whereas telmisartan up-regulated angiotensin II. A second study was conducted to confirm these findings in 5/6 nephrectomy wild-type and genetically deficient DPP-4 rats treated with linagliptin or placebo. Linagliptin therapy in wild-type rats was as effective as DPP-4 genetic deficiency in terms of albuminuria reduction. Thus, linagliptin showed comparable efficacy to telmisartan in preventing CKD progression in non-diabetic rats with 5/6 nephrectomy. However, the underlying pathways seem to be different. Copyright (C) 2016, International Society of Nephrology. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).}, language = {en} } @misc{OngvonWebskyHocher2015, author = {Ong, Albert C. M. and von Websky, Karoline and Hocher, Berthold}, title = {Endothelin and Tubulointerstitial Renal Disease}, series = {Seminars in nephrology}, volume = {35}, journal = {Seminars in nephrology}, number = {2}, publisher = {Elsevier}, address = {Philadelphia}, issn = {0270-9295}, doi = {10.1016/j.semnephrol.2015.03.004}, pages = {197 -- 207}, year = {2015}, abstract = {All components of the endothelin (ET) system are present in renal tubular cells. In this review, we summarize current knowledge about ET and the most common tubular diseases: acute kidney injury (AKI) and polycystic kidney disease. AKI originally was called acute tubular necrosis, pointing to the most prominent morphologic findings. Similarly, cysts in polycystic kidney disease, and especially in autosomal-dominant polycystic kidney disease, are of tubular origin. Preclinical studies have indicated that the ET system and particularly ETA receptors are involved in the pathogenesis of ischemia-reperfusion injury, although these findings have not been translated to clinical studies. The ET system also has been implicated in radiocontrast-dye-induced AKI, however, ET-receptor blockade in a large human study was not successful. The ET system is activated in sepsis models of AKI; the effectiveness of ET blocking agents in preclinical studies is variable depending on the model and the ET-receptor antagonist used. Numerous studies have shown that the ET system plays an important role in the complex pathophysiology associated with cyst formation and disease progression in polycystic kidney disease. However, results from selective targeting of ET-receptor subtypes in animal models of polycystic kidney disease have proved disappointing and do not support clinical trials. These studies have shown that a critical balance between ETA and ETB receptor action is necessary to maintain structure and function in the cystic kidney. In summary, ETs have been implicated in the pathogenesis of several renal tubulointerstitial diseases, however, experimental animal findings have not yet led to use of ET blockers in human beings. (C) 2015 Elsevier Inc. All rights reserved.}, language = {en} } @article{DschietzigKrauseRelleHennequinetal.2015, author = {Dschietzig, Thomas Bernd and Krause-Relle, Katharina and Hennequin, Maud and von Websky, Karoline and Rahnenfuhrer, Jan and Ruppert, Jana and Groena, Hans Juergen and Armbruster, Franz Paul and Bathgate, Ross A. D. and Aschenbach, Joerg R. and Forssmann, Wolf-Georg and Hocher, Berthold}, title = {Relaxin-2 does not Ameliorate Nephropathy in an experimental model of Type-1 Diabetes}, series = {Kidney \& blood pressure research : official organ of the Gesellschaft f{\"u}r Nephrologie}, volume = {40}, journal = {Kidney \& blood pressure research : official organ of the Gesellschaft f{\"u}r Nephrologie}, number = {1}, publisher = {Karger}, address = {Basel}, issn = {1420-4096}, doi = {10.1159/000368484}, pages = {77 -- 88}, year = {2015}, abstract = {Background/Aims: In diabetic nephropathy (DN), the current angiotensin-II-blocking pharmacotherapy is frequently failing. For diabetic cardiomyopathy (DC), there is no specific remedy available. Relaxin-2 (Rlx) - an anti-fibrotic, anti-inflammatory, and vasoprotecting peptide - is a candidate drug for both. Methods: Low-dose (32 mu g/kg/day) and high-dose (320 mu g/kg/day) Rlx were tested against vehicle (n = 20 each) and non-diabetic controls (n = 14) for 12 weeks in a model of type-1 diabetes induced in endothelial nitric oxide synthase knock-out (eNOS-KO) mice by intraperitoneal injection of streptozotocin. Results: Diabetic animals showed normal plasma creatinine, markedly increased albuminuria and urinary malonyldialdehyde, elevated relative kidney weight, glomerulosclerosis, and increased glomerular size, but no relevant interstitial fibrosis. Neither dose of Rlx affected these changes although the drug was active and targeted plasma levels were achieved. Of note, we found no activation of the renal TGF-beta pathway in this model. In the hearts of diabetic animals, no fibrotic alterations indicative of DC could be determined which precluded testing of the initial hypothesis. Conclusions: We investigated a model showing early DN without overt tubulo-interstitial fibrosis and activation of the TGF-beta-Smad-2/3 pathway. In this model, Rlx proved ineffective; however, the same may not apply to other models and types of diabetes.}, language = {en} } @article{ReichetzedervonWebskyTsuprykovetal.2017, author = {Reichetzeder, Christoph and von Websky, Karoline and Tsuprykov, Oleg and Samarin, Azadeh Mohagheghi and Falke, Luise Gabriele and Putra, Sulistyo Emantoko Dwi and Hasan, Ahmed Abdallah Abdalrahman Mohamed and Antonenko, Viktoriia and Curato, Caterina and Rippmann, Joerg and Klein, Thomas and Hocher, Berthold}, title = {Head-to-head comparison of structurally unrelated dipeptidyl peptidase 4 inhibitors in the setting of renal ischemia reperfusion injury}, series = {British journal of pharmacology : journal of The British Pharmacological Society}, volume = {174}, journal = {British journal of pharmacology : journal of The British Pharmacological Society}, publisher = {Wiley}, address = {Hoboken}, issn = {0007-1188}, doi = {10.1111/bph.13822}, pages = {2273 -- 2286}, year = {2017}, abstract = {BACKGROUND AND PURPOSE Results regarding protective effects of dipeptidyl peptidase 4 (DPP4) inhibitors in renal ischaemia-reperfusion injury (IRI) are conflicting. Here we have compared structurally unrelated DPP4 inhibitors in a model of renal IRI. EXPERIMENTAL APPROACH IRI was induced in uninephrectomizedmale rats by renal artery clamping for 30 min. The shamgroup was uninephrectomized but not subjected to IRI. DPP4 inhibitors or vehicle were given p. o. once daily on three consecutive days prior to IRI: linagliptin (1.5 mg.kg(-1).day(-1)), vildagliptin (8mg.kg(-1).day(-1)) and sitagliptin (30 mg.kg(-1).day(-1)). An additional group received sitagliptin until study end (before IRI: 30 mg.kg(-1).day(-1); after IRI: 15mg.kg(-1).day(-1)). KEY RESULTS Plasma-active glucagon-like peptide type 1 (GLP(-1)) increased threefold to fourfold in all DPP4 inhibitor groups 24 h after IRI. Plasma cystatin C, a marker of GFR, peaked 48 h after IRI. Compared with the placebo group, DPP4 inhibition did not reduce increased plasma cystatin C levels. DPP4 inhibitors ameliorated histopathologically assessed tubular damage with varying degrees of drug-specific efficacies. Renal osteopontin expression was uniformly reduced by all DPP4 inhibitors. IRI-related increased renal cytokine expression was not decreased by DPP4 inhibition. Renal DPP4 activity at study end was significantly inhibited in the linagliptin group, but only numerically reduced in the prolonged/dose-adjusted sitagliptin group. Active GLP(-1) plasma levels at study end were increased only in the prolonged/dose-adjusted sitagliptin treatment group. CONCLUSIONS AND IMPLICATIONS In rats with renal IRI, DPP4 inhibition did not alter plasma cystatin C, a marker of glomerular function, but may protect against tubular damage.}, language = {en} }